The vibration voice coils of traditional moving-coil speakers comprise a voice coil body and voice coil lead wires. The voice coil lead wires usually appear in two forms. One is that the voice coil lead wires are attached to the diaphragm, but this method will easily cause the unbalance of the vibration system and the polarization of the diaphragm. The other is that the voice coil lead wires are suspended between the diaphragm and the housing, but this method has very strict requirements on the radian and height of the voice coil lead wires, as well as the symmetry of the negative and positive lead wires; otherwise the voice coil lead wires will easily touch the housing or the diaphragm to cause poor acoustics. In both methods, when the speaker works in a high power mode for a long time, the vibration voice coil and the voice coil lead wires are bent repetitively, and thus there is a potential risk that the voice coil lead wires might be broken, and the product stability is poor.
In addition, the industry has solutions that form a conductive layer using techniques such as electroplating or magnetron sputtering to replace the lead wires of the vibration voice coil. However, the metal particles in the conductive layer formed by the electroplating or magnetron sputtering are arranged sparsely, which causes the defects that the resistance of the conductive layer is too high, and the conductive layer will easily drop off.